Why do I have a daily restart of Tab 2 10.1?

A

AC Question

daily restart of Tab 2 10.1

I have a tab 2 10.1 with a version of 4.0.4 ..at the beginning i had a warning while charging my battery that the battery temperature was too high so charging was paused after a week. It started restarting automatically every 30 mins.
I took it to a repairing store who formatted it all by mistake saying he thought its a software problem.
now, after formatting it still restarts just not as frequently.
PS: i use unofficial charger.
what could be the problem? is it the old version? because i installed kies 2.3 for updating it.